56 



Dr. Hofmann on the Action of Trichloride. [Mar. 22, 



dually rose from 55° to 78°. The last portion which came over was pure 

 trichloride of phosphorus. It was obvious that this substance must have 

 played a part in the formation of the new compound. 



I therefore submitted phenylacetamide to the action of trichloride of 

 phosphorus. The new body was formed, but in very unsatisfactory quan- 

 tity. The result of the experiment was essentially different when phenyl- 

 acetamide and aniline in varying proportions were jointly submitted to the 

 action of trichloride of phosphorus. The amount of substance obtained 

 varied with the composition of the mixture, and appeared greatest when 

 the mixture was made in the proportion of one part of trichloride of phos- 

 phorus, two parts of aniline, and three parts of phenylacetamide. Hence 

 the reaction had taken place according to the following equation : 



3 C3 H, N + 3 Hg NO + PCI3 = 3 C,, H,, + H3 PO3 + 3 HCl. 



Perfectly similar results were obtained when a proportionate quantity of 

 hydrochlorate of aniline was employed instead of aniline in this expe- 

 riment. 



The idea naturally presented itself to produce the same result without 

 taking the trouble of preparing and purifying the phenylacetamide by in- 

 cluding its preparation in the very process of forming the new compound. 

 For this purpose 6 molecules of aniline were added to 3 molecules of chlo- 

 ride of acetyl, and the dense liquid thus ^obtained mixed with 1 molecule 

 of trichloride of phosphorus. The result could not have been better : 



6 C3 H, N + 3 C, H3 001 + FCI3 = 3 C,, H,, N, + H3 PO3 + 6 PICl. 



A simple additional step and the true mode of preparing the substance, 

 and with it the general method for the production of an endless variety of 

 analogous bodies, was found. Evidently it was not even necessary to pre- 

 pare the chloride of acetyl separately. The new body must be as easily 

 obtained by the direct action of trichloride of phosphorus on aniline and 

 acetic acid. The mixture had only to be made in such a manner that, after 

 transforming the acetic acid into chloride of acetyl, there was a sufficient 

 amount of trichloride of phosphorus left to perform the rest of the work. 

 In this case, therefore, 6 molecules of aniline and 3 molecules of acetic acid 

 had to be added to 2 molecules of trichloride of phosphorus, 



6 0, II, N + 3 H, O, + 2 PCl3=: 3 C,, II,, N, -j- 2 H3 PO3 -f G HCl . 



The reaction is violent, and the operation must be performed with care. 

 The substances are mixed according to the above equation. For this 

 purpose three parts by weight of aniline are added to one part of acetic 

 acid and into the mixture surrounded by cold water two parts of trichloride 

 of phosphorus are slowly poured ; in which proportion the latter compound 

 is in slight excess. The tenacious fluid thus obtained is then heated for a 

 couple of hours to 160°. On cooling, it solidifies to a hard, friable, trans- 

 lucent, resinous mass of a light-brown colour, which dissolves in boiling 

 water almost without residue, leaving only traces of an amorphous yellow 



